Dispensing device



Sept. 26, 1939. R. K. HOPKINS 2,174,175

DISPENSING DEVICE Original Filed Nov. 5, 1936 3 Sheets-Sheet 1 FIG.I

INVENTOR ROBERT K. HOPKINS ATTORNEY Sept. 26, 1939. R. K. HOPKINS 2,174,175

DISPENSING DEVICE Original Filed Nov. 5, 1956 I5 Sheets-Sheet 2 FIG. 2

I22 42 INVENTOR ROBERT K. HOPKINS A ORNEY Sept. 26, 1939. R K, HOPKINS 2,174,175

DISPENS ING DEVICE Original Filed Nov. 5, 1936 3 Sheets-Sheet 3 FIG. 3

I23 I24 I25 I28 I I 1 1 6 I I 94 0 67 a @b m H 69 I 00 5 I03 H 1; ,1 6 I A o5 (9' I06 INVENTOR ROBERT K. HOPKINS ATTORNEY Patented Sept. 26, 1939 UNITED STATES PATENT OFFICE M. W. Kellogg 00., New York, N.

ration of Delaware Y., a corpo- Orlginal application November 5, 1936, Serial No. 109,292. Divided and this application April 16, 1938. Serial No.

4 Claims.

This invention relates, in general, to the electric fusion oi metals, and has particular reference to an improved apparatus for carrying out operations of this type.

This application is a division of my copending application Serial No. 109,292, filed November 5, 1936.

In the present practice of electric welding the deposition of metal is ordinarily carried out by 1. the use of consumable electrodes. These electrodes may be bare or covered but in any case, the metallic component thereof includes all or substantially all of the constituents required to produce the desired deposited metal. Thus, electrode metal is generally of special analysis and by reason of this fact and the fact that it is usually produced in small quantities is considerably more expensive than metal of generally similar analysis in the usual commercial iorms. In any event, electrode metal is usually much more expensive than the constituents thereof in their readily available commercial forms.

In my copending application, Serial No. 101,- 103 tiled September 16, 1936, I have disclosed and claimed a method, and apparatus for carrying it out in practice, in which the constituents of the desired deposited metal in the readily available commercial forms are supplied to the welding gap in separately controlled streams so that with any set of constituents weld metals of wide variation in analysis may easily be deposited. Preferably, some of the constituents are supplied in the form of a hollow metallic electrode and the remainder are supplied in the form of powder, granules, pellets or wire and fed to the welding gap through the hollow electrode. Thus, for instance, when it is desired to deposit an iron-chrome alloy upon carbon steel base metal the hollow electrode is made of mild steel and the chromium is supplied as ferro-chrome. With this set of constituents, a wide range of iron-chrome alloys may be deposited.

The apparatus of this invention is in the nature of an improvement over the apparatus of my copending application, above identified.

It is the primary object of this invention to provide an apparatus of the character mentioned that includes an improved arrangement for feeding and for controlling the rate of feed of the stream of material passed to the welding gap through the hollow electrode.

The further objects and advantages of this invention will be apparent from the following description and claims taken in connection with the accompanying drawings forming a part of this application, in which,

Fig. 1 is a front elevation showing the welding machine depositing a welded veneer upon a workpiece.

Fig. 2 is an elevation view showing the feed mechanism for one of the weld metal constituents; and

Fig. 3 is a sectional view taken along lines 3-3 of Pig. 2.

Referring to Fig. 1, the welding machine comprises a supporting frame Ill, to the lower end of which is attached a welding head ll. Welding head Il may be of any preferred construction and arrangement but should include all oi the usual elements and devices necessary for successful operation, these elements and devices, for the purposes of this application being considered as located in back of the panel of welding head H. The upper portion of frame I supports a platform [2 upon which is positioned an automatic feeding mechanism iii, to be fully described hereinafter. The welding machine is positioned above workpiece i4 and may be arranged for movement relative to workpiece I. On the other hand, the welding machine may be fixedly positioned and workpiece it supported to allow it to be moved relative to the welding machine, or both the welding machine and the workpiece l4 may be supported for desired movement. It is to be understood, that all structural requirements necessary to maintain the various elements in their proper relationship have been provided, despite their omission from the drawings for the sake of convenience and clarity.

The apparatus disclosed, includes three electrodes l5, l6 and l! which together with the material passed through hollow electrode l1 supply all of the constituents for the required deposited metal. The spacing of the electrodes is such that they deposit their metal in a common pool [8. The pool i8 is formed into a continuous band by the relative movement of the workpiece I4 and the welding machine.

As particularly shown in Fig. 1 the ends of electrodes l5, l6 and H are submerged in a flux blanket i9 that is formed between members disposed along the electrode path. The purpose and composition of flux blanket l9 as well as the band forming operations are disclosed at length in my copending application above identified, and need not be repeated here.

It is to be understood that while a veneering operation has been illustrated, the apparatus of this invention is not limited thereto and can be Eli used equally well in connection with any of the known welding operations.

' The composition of electrodes l5, l6 and H, as well as the composition of the material passed through hollow electrode I 1, which in the rest of this application will be referred to as the granular material, will depend on the composition of the weld metal it is desired to deposit as well as the composition of the base metal upon which the weld metal is deposited. For instance, if the weld metal is to be an iron-chrome alloy and the base metal a carbon steel, all three electrodes may be of iron, or some may be of iron and others of some cheap readily available ironchrome alloy. When the weld metal desired is a chrome-iron alloy the granular material may be ierro-chrome. When the weld metal desired includes more than one alloying constituent as for instance, when it is a chrome-nickel-iron alloy, the granular material may be a proper mixture of ferro-chrome and metallic nickel or some suitable compound of nickel. In this case, however, the nickel may also be supplied by making one or more of the electrodes of nickel. Electrodes l5 and I6 may be in any preferred form, such as rod or wire. For the purposes of this application they will be considered to be wire and supplied as from a pair of reels mounted on the supporting structure in any preferred manner. Electrode IT is preferably hollow or at least trough-like. When depositing iron alloys in which iron is a major constituent'upon an iron orcarbon steel base metal electrode ii is preferably an iron or a mild steel pipe since both of these articles are cheap and readily available.

Electrodes it and it are positively fed toward workpiece it by means of grooved feed wheels mounted on the shafts of the electrode feed motors 2i and 22.

Pressure rollers 2'3 and 2t serve to hold the electrodes i5 and it against their corresponding feed wheels in order to maintain a firm gripping action on the electrodes at all times. Correct lateral positioning of the three electrodes is maintained by means of the contact nozzle 2%) and the guide block it through which the electrodes pass.

Contact nozzle 25 not only maintains the proper spacing between the electrodes, but also supplies current to them from the current source. ihe nozzle is provided with suitable insulating arrangements so that each electrode may be supplied with current independently of the others. With this arrangement it is possible to control and vary as necessary, the current being supplied to each electrode. When desirable, it is also possible to cut off the current supply to any of the electrodes in order that they may be fed to the welding pool as dead electrodes. It is, of course, apparent that the current may also be supplied from a single source through the contact nozzle to any combination of the electrodes by eliminating the insulating means.

Electrode ill comprises a plurality of easily connectible lengths, two lengths being shown in the drawings although an indefinite number may be used. The separate hollow electrode lengths are adapted to be joined end-to-end by any suitable means, such as the threaded nipple 3G.

The hollow electrode H is positively fed to the welding gap by means of a driving roller, connected to the shaft of the motor 27], that is backed up by a pressure roller 28 diametrically opposed thereto. Correct proportioning of the electrode constituents is maintained by regulating the speed of the feeding motors so that a suitable relationship between the rate of feed of the electrodes and the rate of travel of the welding machine relative to the workpiece may be obtained in order to secure weld metal of the desired analysis. The manner of the obtaining and controlling these and the other essential factors is set out at length in my copending application above identified. The granular material is fed through the hollow electrode ll, the rate of feed being controlled by means of the automatic feeding mechanism l3. The feeding connection between the mechanism I3 and the hollow electrode i1 is maintained by providing a telescopic arrangement between the hollow electrode l1 and a feed pipe 29, the outside diameter of which at least at its bottom end is substantially less than the bore of the hollow electrode, and also less than the bore of tl nipple I8. The upper end of the pipe 29 is fitted into a feed pipe head 3! having a funnel-shaped interior connecting with the hollow center of the feed pipe to form a pathway for the granular material from the feeding mechanism l3 to the hollow electrode. Projecting outwardly on opposite sides of this pipe head 36 are a pair of pins 32 and 33 which support the pipe 29 in a manner to be presently described. As the hollow electrode is consumed in the welding operation it is withdrawn from the feeding pipe 29 until the two become separated, at which time a newhollow electrode length is joined to the remaining portion of the hollow electrode which is being consumed. To expedite this oper- .ation, a second hollow electrode length I1 is constantly kept in readiness so that a rapid change-over may be made, and the new length. ill secured to the upper end of the preceding length ll without interrupting or materially affecting the continuity of the feeding.-

For this purpose, a pipe rack, generally indicated at 34, is provided. It comprises a movable block 35 adapted to slide transversely in a guideway 36 secured to the upper portion of the iramework it directly beneath the platform i2. Secured to the under side of the block 35, and projecting downwardly therefrom in parallel fashion, are a pair of angle iron strips 31 and 38 and, spaced midway therebetween, a strip of U-shaped channel iron 39. A transverse strip ii) is tened across their lower ends to provide a sturdy framework and to maintain the proper lateral spacing.

The forwardly projecting sides of the channel and angle iron strips are provided with a series of slots M, d2, 4!! at their upper ends which act as bearing grooves for the pins 32, 33, 32' and 32 of the feed pipe head 3i and 3i. cut at a slight downward angle so that a slight upward thrust of the feed pipes will cause the same to be forced outwardly to disengage the feed Dine head from the rack.

The idle feed pipe 29 is kept in readiness with a length of hollow electrode i'l thereon, so that a rapid changeover may be made. The pipe ii is held on the feed pipe 29' in either of two ways, by screwing the upper end of the electrode a few turns onto the threaded portion of the feed pipe, projecting from beneath the head M, which portion has the same thread-size as the nipple Sill or by means of a horizontal lever 53 pivoted at M to a plate 45 fitted into the U-channel member 39 at its lower end. The lever 43 is provided, near its free end, with a pair of slots oppositely disposed and or a width greater than the diameter of the feed pipes, but less than the The slots are diameter of the projecting end of the nipple 36. The pivot 44 is spaced midway between the hanging feed pipes 29 and 29' and the slots are spaced from the pivot sufllciently so that by swinging the lever either to the left or right the forward slot may be made to engage its corresponding feed pipe to provide a lateral support for the pipe electrode. The lower support 43 may be used whenever short lengths of hollow electrodes are being used, in which case the electrode, if suspended by its upper threaded portion, might not be within reach of the operator.

The electrode switching operation is accomplished as follows: a length of cable 41 is secured at its ends to a pair of pin members 48 and 49 projecting-from the upper surface of the sliding block 35. The cable passes around pulleys 5| and 52 secured to the upper portion of'the frame work l0, and around pulleys 53 and 54 secured to the welding head I I. A second length of cable 55 passes around a pair of pulleys 56 and 51 and has its ends fastened to cable 41 at points 58 and 59. At its midpoint, the cable 55 is suitably secured to a pin 6| projecting from the back of the U-channel member 39. A shift lever 62, having one end pivotally mounted at 63 to the framework l0 and the other end projecting forwardly to a point within easy reach of the operator, is secured at a point 64 between its ends to the cable 41. Within the rack 34 in the position shown in Fig. 1 the lever 62 will be in its raised position.

When the hollow electrode I! has been consumed sufficiently to cause it to separate from the feed pipe 29, the reserve length of hollow electrode I1 is brought into position for use by pressing down the free end of shift lever 62. From the cable and pulley arrangement shown in the drawings, it is obvious that, as the lever is pushed down, the rack will move to the right. Suitable limiting arrangements may be made so that the rack will move only to a position in which the electrode lengths I1 and I1 are in alinement, or the positioning may be done by hand. The

two electrode lengths are then joined by unscrewing the electrode H from the upper threaded portion of the feed pipe 29' or where' a short length is being added, by releasing the plate member 43 and screwing the nipple 38 at the lower end into the threaded end of the electrode IT. This connection may be made very rapidly without interrupting the continuity of the feeding, it being necessary only to perform the operation before the electrode l1 passes through the guide block 26. During the changeover the flow of the granular material is momentarily interrupted, as will be later described in connection with the feeding mechanism shown in Fig. 2. A new length of hollow electrode I! may then be placed in readiness for use by removing the feed pipe 29 from the rack, which may be done by merely thrusting the same upwardly to release the pivot pins 32 and 33 from their supports and placing a new electrode length thereon, or by tilting the feed pipe outwardly at its lower end and thrusting a length of hollow electrode on the latter. The plate 43 is then swung about its pivot 44 to a position where the opposite slot in the free end will engage the feed pipe 29 and act as a support for the new electrode length.

In order to maintain a substantially continuous flow of the granular material through the electrode, and to prevent the material from clogging in the electrode, a vibrator 60 is positioned on contact nozzle 25. The vibrator may be of any well-known type, its function being to impart a continuous tapping action to the hollow electrode to shake loose any particles of material that may adhere to the inner surface of the electrode and clog the flow of granular material therethrough. The vibrator illustrated is of a compressed air type, although any mechanical or electrical type might be used in its stead.

Referring now to Fig. 2 the feed mechanism I3 will be described. It comprises a housing 65 mounted on a base plate 66 which rests upon the platform 12. Centrally located within the housing is a vertical shaft 61 supported by crossmember bearing plates 68 and 69 secured to the sides of the housing. The upper end of the shaft is set in a recess in the bearing plate 68 and the lower end projects through an opening in plate 69 where it is joined, by means of a coupling sleeve H, to the shaft of a gear reduction box 12. The driving shaft 13 of the gear reduction box is connected to a motor 13 shown in dotted lines and located at the rear of the housing on the platform l2. The motor includes suitable speed varying means so that the driving rate may be varied at will. The speed varying means may take the form of a variable speed motor or, in lieu thereof, any of the well known'arrangements of variable speed transmission. Longitudinal movement of the shaft 61 downwardly is prevented by means of a stepped portion 14 which rests upon the bearing plate 69. Mounted on the shaft 61 intermediate the cross-members 68 and 69 is a flanged disc 15. The shaft is formed of greater diameter below the disc in order to provide a shoulder 16 upon which the disc may rest. A suitable arrangement, such as a pin or keyway, is provided so that the disc will rotate integral with the shaft 61. The flanged portion 11 of the disc 15 is provided with a series of holes 18 equispaced about the disc, ten holes are used in the present embodiment. These holes serve as carrying receptacles for the granular material which is supplied from the storage container 19, mounted on a bracket projecting from the bearing plate 68, and having a funnel-shaped bottom. A pipe 8| directs the granular material from the container to the surface of the disc flange 11 and into the holes 18 as they pass directly beneath the lower opening of the pipe. A felt wiper sleeve 82 connected to the lower end of pipe 8| by a clamp 38 contacts the flange surface. As the disc rotates the sleeve holds back the excess particles and permits a level receptacle full of granular particles to be conveyed.

While rotating from the point of filling to the point where discharge is to take place, the metal granules are retained in the holes 18 by means of individual dump-valves 84 disposed adjacent each hole on the under side of the disc. The valve mechanism comprises a trap door 85 pivoted at 86 to a block 81 secured to the underside of the disc by a screw 88. A lever 89, disposed on a radial line, has its outer end connected, through a link ill, to a projecting portion 92 of the trap door 85, and its inner end pivotally secured at 93 to the projecting head of a bolt 94 extending through the disc. The lever 89 comprises two identical parallel members held apart by spacing blocks 95 and 96. The trap 'door 85 is normally held in its closed position by means of a spring 91 acting upon an operating plunger 98 extending through the disc. The lower end of the plunger is pivotally secured at 99 to the lever 89 at a point intermediate its ends. The

spring 91 is disposed in a recess I having a ledge portion IOI at its lower end. The spring is held under compression between the ledge portion IOI and the mushroom head I02 of the operating plunger 98.

As the shaft 51 rotates, the head I02, which normally projects a substantial distance above the upper surface of the disc, engages a roller I03, pivoted at I04 to a bracket I05 mounted on the cross member 68. When the disc reaches a position where a hole I8 is directly forward, the plunger head I02 will be urged downwardly by the roller I03. This causes the trap door 85 to open, thus releasing the granular material. As the plunger head passes from beneath the roller the trap door 35 closes under the action of the spring 91. It is obvious that as the disc rotates there will be an intermittent discharge oi granular material, the rate of which is determined and controlled by the speed varying means of the operating motor.

To prevent small particles of the granular material from adhering to the surface of the trap door or under side of the disc, and thus preventing the trap door from closing to form a good seal, a wiping brush may be placed in convenient position on the front of the framework to wipe the particles off door and disc immediately iollowing the dumping operation and before the trap door has had an opportunity to close. An additional safeguard to insure closing of the trap door sufficiently to prevent leakage has been provided in the form of a contact ring tilt supported on the cross member I59 by two non-conductive supports III'I and its and connected to a source of potential. The ring its is cut away for a substantial portion of its circumference, as shown in Fig. 3, to permit the lever 89 to be lowered when at its discharge position. After discharge takes place, the lever 89 ordinarily is pulled up wardly. However, should the mechanism become jammed, or for any reason fail to function prop erly and the trap door remains open, the lower forward end of the lever will touch the contact ring. By grounding the disc and inserting a warning device in circuit the operator may be apprised of the improper operation of the valve. The approach end of the ring Itii is curved downwardly at I09 to prevent the lever from catching on the edge of the ring when it becomes stuck in its lowermost position. The inclined portion of the ring also serves to start the closing operation of the lever when the latter is below the plane of the ring. Since the ring is positioned so that it barely misses the valve mechanism in its closed position, the ring itself will in many cases, release the stuck valve.

Below the bearing plate I59 are two funnel shaped guides III and H2 for catching the granular material. The guide III is placed forward of the bearing plate and is secured thereto at its upper end. The lower end terminates in a circular opening fitted to a pipe II 3 extending through the support I2. This funnel is for directing the granules to the hollow electrode. The second funnel member is disposed to the rear of hearing plate 89 and terminates at a pipe Hi l at the rear of the apparatus. This funnel is for catching the excess particles that are wiped off the disc in the leveling operation. These particles may be caught in a receptacle placed beneath the pipe IIfi and replaced in the storage container "Iii.

The sliding block 35 has a projecting portion M5 on either side adapted. to engage and slide along the U-shaped channel guides 30 and 30'. The block 35 has a longitudinal groove IIB out in its upper surface and at each end of the groove there is a funnel shaped hole III projecting vertically through the block. Outlet pipes III and I I8 are fitted into the lower side of the block at the bottom of the holes. It will be observed that the outlet pipe H8 projects into the opening in the feed pipe head 3|. As shown in the drawings the rack is in position for direct feeding into pipe electrode II.

As the rack is shifted to its opposite position by means of the cable II, the pipe II3 passes along the groove II6. A felt sleeve H9 is fitted on the lower end of the pipe H3 and projects below its end so as to engage the surface I2I at the bottom of the groove. The i'elt sleeve serves as a wiper to prevent particles from spilling over the surface oi the groove and also to seal the material in the pipe II3 during the changeover operation. During the changeover it is not necessary to stop the feeding apparatus since the particles may be allowed to accumulate inside the pipe II3. Upon reaching the opening on the opposite side of the groove the entire accumulation will dump.

The construction of the feed pipe head is also clearly shown in this figure. The block M has a cylindrical opening I22 tapering at its lower end. The upper threaded end of the iced pipe 29 is screwed into a threaded opening in the lower end of the block BI. The method of supporting the block by means of the pins 32 and in grooves 55E and I2 formed in the sides of the angle iron and channei iron frames is also clearly shown.

Fig. 3 shows a plan view of the feeding apparatus with the storage container removed and portions broken away for the sake of clarity.

The positioning of the storage container bracket i222 and the valve operating roller bracket I05 on the cross member 68 is clearly shown. To insure accurate leveling of the particles of granular material in the holes I8 and to keep the upper surface of the flange portion II of the disc free from loose particles, an additional safeguard in the form. of three wiper brushes is provided.

The brushes I23, I24, and I25 are mounted on' arms I26 extending from a bracket I2I fastened to the side of the housing. These wipers may be made of felt or other suitable material and are disposed to hear lightly on the surface of the disc. The wipers are set at an angle so that the particles will be brushed off the outer edge of the flange as the disc rotates. The particles brushed off are caught in the funnel-shaped guide H2 and directed through the outlet I28 to the outlet pipe IIE, shown in Fig. 2.

While this invention has been shown in but one form, it will be obvious to those skilled in the art that it is not so limited but is susceptible to various changes and modifications without departing from the spirit thereof, and it is desired therefore that only such limitations shall be placed thereon as are imposed by the prior art or are specifically set forth in the appended claims.

I claim:

l. A metering device for feeding metal in arc welding apparatus, a source of material, a rotatable disc having a plurality of holes therethrough, individual spring operated closure means adapted to close the bottoms of said holes to form a plurality of material receptacles, said receptacles losing arranged to travel in a circular path between'said source and a point of discharge, the feeding rate of material from said source exceeding the conveying rate along said path, means for trimming ofl deposited material in excess of the volume capacity of said receptacles, means for successively opening said closure means at said discharge point to release said material, and a signalling device adapted to operate when said closure means opens at any position along said path other than said discharge point.

2. A metering device for feeding metal in arc welding apparatus, a source of material, a rotatable disc having a plurality of holes therethrough, individual spring operated closure means cooperating with said holes to form a plurality of material receptacles, said receptacles being arranged to travel in a circular path between said source of material and a point of discharge, the feeding rate of material from said source substantially exceeding the conveying rate of material along said path, means for trimming oiI deposited material in excess of the volume capacity of said receptacles, means for successively opening said closure means at said discharge point to release said material, and a signalling device comprising an insulated contact segment disposed adjacent said closure means and arranged to be contacted by said closure means when the latter open at any point other than said discharge point.

3. A metering device for feeding metal in arc welding apparatus comprising, material supply means, a disc supported for rotation about a' substantially vertical axis, said disc provided with holes adjacent its periphery into which material from said supply means is adapted to discharge, a swingable closure for the bottom of each of said holes, operable means connected to each of said closures for swinging said closures into andout of closing relation with their respective holes, and actuating means for said operable means, said actuating means including a member for each of said closures adapted to extend through said disc and a spring constantly urging said members through said disc whereby said closures are normally held in closing relation with their respective holes, said members being spaced on a circle concentric with said axis, and a fixedly positioned roller adapted to ride on said disc during the rotation thereof and to depress said members as they pass beneath it to swing said closures out of closing relation with their respective holes.

4. A metering device for feeding metal in arc welding apparatus comprising, material supply means, a disc supported for rotation about a substantially vertical axis, said disc having a pluralityof holes spaced adjacent the periphery thereof into which material from said supply means is adapted to discharge, a closure for the bottom of each of said holes pivoted to the bottom of said disc, a linkage for each of said closures, said linkages being radially disposed and having one end pivoted to the bottom of said disc and the other end pivoted to their respective closures, an operating member for each of said linkages, each of said operating members passing through said disc and having one end pivoted to its linkage and the other end adapted to extend above the top of said disc, spring means urging each of said other ends of said members above the disc to normally maintain said closures against their respective holes, and a fixedly positioned roller positioned to ride over said other ends of said members to depress the same and to swing said closures to open the bottom of their respective holes.

ROBERT K. HOP'HNS. 

